1. Technical Field
The present invention relates to a heart occluder supporter, and, in particular, to an occluder supporter which, through its provision to the valves of a mammalian heart, prevents blood from refluxing back through the valve.
2. Related Art
There are four valves present in the mammalian heart. They are the tricuspid valve, the mitrial valve, the pulmonary valve, and the aortic valve.
The tricuspid valve is the valve located in the space between the right atrium and the right ventricle. The mitrial valve is the valve located in the space between the left atrium and the left ventricle. The pulmonary valve is the valve located in the space between the right ventricle and the pulmonary artery. The aortic valve is the valve located in the space between the left ventricle and the aorta. Of these, the tricuspid valve and the mitrial valve are called the ventricular valves.
An example of the mitrial valve and the aortic valve and an explanation of their function follows.
First, the case where the function of the mitrial valve is normal will be considered. During the contractions phase of the left ventricle, the mitrial valve is completely shut and the blood within the left ventricle is pumped to the aortic artery. During the relaxation phase of the left ventricle, the mitrial valve is completely open and blood flows into the left ventricle from the left atrium. If, for some reason, a situation occurs wherein the occluder of the bicuspid enlarges, or the chordae tendineae become extended or torn, the mitrial valve is unable to close completely, thereby resulting in a condition where a section of the valve aperture of the mitrial valve remains open. As a result, the opening and closing action of the mitrial valve is imperfect, and a phenomena wherein blood refluxes from the left ventricle into the left atrium (hereafter stated as valve reflux) occurs.
Next, the case where the function of the aortic valve is normal will be considered. During the contraction phase of the left ventricle, the aortic valve is completely open and the blood within the left ventricle is pumped to the aortic artery. During the relaxation phase of the left ventricle, the aortic valve is completely shut and blood flows into the left ventricle from the left atrium. As in the case given above for the mitral valve, if for some reason, a situation occurs wherein the occluder of the aortic valve enlarges, or the valve tip atrophies, the aortic valve is unable to close completely, thereby resulting in a condition wherein a section of the valve aperture of the aortic valve remains open. As a result, the opening and closing action of the valve is imperfect, and a phenomena wherein blood refluxes from the aortic artery to the left ventricle (hereafter stated as valve reflux) occurs.
Valval transplant, valval suturing, and valvoplasty, are among the conventional methods of treatment to correct valve reflux.
Valval transplant is the method of excising the chordae tendineae of the valve tip and attaching an artificial valve or a donor valve to the remaining occluder. Valval suturing is the method of preserving the actual valve itself through suturing the occluder by sewing together one end of the occluder, or through setting the occluder by sewing on a ring to the occluder.
A variety of defects, however, are present in these methods.
For example, in valve substitution, the artificial or donor valve used is considerably expensive and has a short lifetime. Furthermore, in valve suturing and valvoplasty it is not possible to easily prevent valve reflux from occurring through the middle portion of the valve.